TABLE 2a 



Spike recoveries and limits of detection for water and low volume air samples. 



Sample ng a-HCH 



Type Spiked <7f Recovery LOD" 



Y-HCH 

 % Recovery LOD- 



Water" 10-17 119.95,81(98^ 0.10 ng/L 89,87,82(86)^ 0.10 ng/L 

 Air 17 85.76(80)' 20pg/m' 



a. LODbyECD. 



b. Preconcentration by liquid-liquid and bonded-phase extraction. 



c. Mean. 



TABLE 2b 



Spike recoveries and limits of detection for high volume air samples 



The HCH " s mean concentrations in high volume air samples 

 detemiined by ECD and EIMS and chlordanes deteimined by 

 EIMS and NIMS are not significantly different (Table 3b) 

 (t-test, a= 0.05). Alpha-HCH was quantified using both the 

 low and high volume air collections. Comparison of the 

 average concentration of CrHCH by both methods reveals no 

 significant differences (t-test, a = 0.05) in mean 

 concentrations, 266 pg/m' by high volume and 25 1 pg/m' by 

 low volume. 



Liquid-liquid extraction and C„ cartridge methods of 

 preconcentration were compared at four stations. 

 Concentrations of a-HCH averaged 2.57 ± 0.16 ng 1 ' by 

 extraction and 2.60 ± 0.12 ng 1 ' by bonded-phase cartridges, 

 with no significant differences (T-test, a= 0.05). Similarly, 

 y-HCH averaged 0.70 ± 0.09 ng 1' using extraction and 

 0.61 ±0.07 ngl' using bonded-phase cartridges, again revealing 

 no significant differences. As comparable levels of HCH were 

 found regardless of the preconcentration method, water at all 

 remaining stations was analyzed using the liquid-liquid 

 extraction method. 



Atmospheric OC Concentrations 



Airborne OC concentrations for the HCH's, chlordanes, 

 and FCC found over the Bering and Chukchi Seas are listed in 

 Table 3, DDT' s and PCB in Table 4, both using the high volume 

 system, and Table 5 shows concentrations of HCB and a-HCH 

 for the low volume system. Concentrations of HCB and the 



HCH's found over the Bering and Chukchi Seas are compared 

 with literature values in Table 6. Concentrations of a-HCH 

 were 200 pg m ' lower in the Bering and Chukchi Seas than in 

 the Beaufort Sea, and y-HCH was 25 pg m ' higher than levels 

 found in the Beaufort Sea in 1986 and 1987 (Patton et ai. 

 1 989 ). Tanabe and Tatsukawa (1980) determined atmospheric 

 concentrations ofHCHoverthe Bering Sea in July 1979. They 

 reported the mean Z HCH as 920 pg/m' with a wide range of 

 460-1 ,700 pg/m', higher than the mean Z HCH found duting 

 thiscruise of 323 pg/m'. The a-HCH/y-HCH atmospheric ratio 

 has been suggested as a "marker' for recent atmospheric 

 transport of these pollutants (Pacyna&Oehme, 1988). During 

 this expedition, the a-HCH/y-HCH ratio ranged from 2.0-3.7 

 and averaged 2.9. This is much lower than the value of 18 

 found in the Canadian Arctic in August 1986 (Patton et ai. 

 1989). Pacyna and Oehnie (1988) referred to low 

 a-HCH/y-HCH of 1 —1 as a "European" source. Five-day back 

 air trajectories for 6 of the days at sea (Fig. 1 ) show much of the 

 sampled air to have been over the Soviet Union (trajectories 

 D,E,F); however, no differences in a-HCH/y-HCH were 

 observed for air masses from the North Pacific (trajectories B 

 and C, a/y=3.3) compared to those passing over the Soviet 

 Union (trajectories D,E,F,04'y=3.1). Pacyna and Oehme( 1988) 

 suggested that high a-HCH/y-HCH ratios (>100) found at Ny 

 Alesund in the Norwegian Arctic niay implicate a source froin 

 the Soviet Union, which is inconsistent with reported use of the 

 90% lindane formulation in the USSR (IRPTC, 1983). 



270 



